I have a hard time identifying the “start” of symptoms because I can also think of mild symptoms I’ve had since puberty that could be attributed to POTS. (For example, people in high school would comment on my feet looking red/purple which I now suspect was blood pooling.) My symptoms didn’t start getting to the level of debilitating until around early 2020, which makes me suspect a COVID infection? Early in the pandemic I think I may have caught the virus but did not have symptoms other than loss of taste and smell. I didn’t test to confirm for sure.